package com.gitee.zw.irmp.common.utils;

import java.io.*;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ZipUtils {

    private static final int BUFFER_SIZE = 2 * 1024;

    public static void zip(String srcDir, File zipFile) throws FileNotFoundException {
        FileOutputStream fos1 = new FileOutputStream(zipFile);
        zip(srcDir, fos1);
    }

    /**
     * 压缩成ZIP文件
     *
     * @param srcDir 文件路径
     * @param out    压缩文件输出流
     */
    public static void zip(String srcDir, OutputStream out) throws RuntimeException {
        long start = System.currentTimeMillis();
        ZipOutputStream zos = null;
        try {
            zos = new ZipOutputStream(out);
            File sourceFile = new File(srcDir);
            compress(sourceFile, zos, sourceFile.getName());
            long end = System.currentTimeMillis();
            //System.out.println("压缩完成，耗时：" + (end - start) +" ms");
        } catch (Exception e) {
            throw new RuntimeException("zip error from ZipUtils", e);
        } finally {
            if (zos != null) {
                try {
                    zos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public static void zip(List<File> srcFiles, File zipFile) throws FileNotFoundException {
        FileOutputStream fos1 = new FileOutputStream(zipFile);
        zip(srcFiles, fos1);
    }

    /**
     * 压缩成ZIP
     *
     * @param srcFiles 需要压缩的文件列表
     * @param out      压缩文件输出流
     */
    public static void zip(List<File> srcFiles, OutputStream out) throws RuntimeException {

        long start = System.currentTimeMillis();
        ZipOutputStream zos = null;
        try {
            zos = new ZipOutputStream(out);
            for (File srcFile : srcFiles) {
                byte[] buf = new byte[BUFFER_SIZE];
                zos.putNextEntry(new ZipEntry(srcFile.getName()));
                int len;
                try (FileInputStream in = new FileInputStream(srcFile)) {
                    while ((len = in.read(buf)) != -1) {
                        zos.write(buf, 0, len);
                    }
                    zos.closeEntry();
                }
            }
            long end = System.currentTimeMillis();
            System.out.println("压缩完成，耗时：" + (end - start) + " ms");
        } catch (Exception e) {
            throw new RuntimeException("zip error from ZipUtils", e);
        } finally {
            if (zos != null) {
                try {
                    zos.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    /**
     * 递归压缩方法
     *
     * @param sourceFile 源文件
     * @param zos        zip输出流
     * @param name       压缩后的名称
     */
    private static void compress(File sourceFile, ZipOutputStream zos, String name) throws Exception {
        byte[] buf = new byte[BUFFER_SIZE];
        if (sourceFile.isFile()) {
            // 向zip输出流中添加一个zip实体，构造器中name为zip实体的文件名
            zos.putNextEntry(new ZipEntry(name));
            // copy文件到zip输出流中
            int len;
            try (FileInputStream in = new FileInputStream(sourceFile)) {
                while ((len = in.read(buf)) != -1) {
                    zos.write(buf, 0, len);
                }
                // Complete the entry
                zos.closeEntry();
            }
        } else {
            File[] listFiles = sourceFile.listFiles();
            if (listFiles == null || listFiles.length == 0) {
                // 空文件夹的处理
                zos.putNextEntry(new ZipEntry(name + "/"));
                // 没有文件，不需要copy
                zos.closeEntry();
            } else {
                for (File file : listFiles) {
                    // 注意：file.getName()前面需要带上父文件夹的名字加一斜杠,保留原来的文件结构
                    compress(file, zos, name + "/" + file.getName());
                }
            }
        }
    }
}
